Method for securing forms from a position of safety

ABSTRACT

A MECHANISM FOR SECURING FORMS IN POSITION TO DEVELOP A CONCRETE STRUCTURE IN SUCCESSIVE POURS, INCLUDING AN ANCHOR EMBEDDED IN THE PREVIOUS POUR, AND A COUPLING UNIT ON THE FORM, THE COUPLING UNIT BEING EXTENDABLE TO A POSITION FOR ENGAGEMENT WITH MEANS FIXED WITH RESPECT TO THE ANCHOR WHEN THE FORM IS SET BACK FROM THE FORMED FACE OF THE CONCRETE, THE COUPLING UNIT BEING RETRACTABLE BY A DEVICE CONTROLLABLE FROM THE FACE SIDE OF SAID FORM TO DRAW THE FORM INTO ENGAGEMENT WITH THE FORMED FACE, AND THE METHOD OF SECURING A FORM FROM THE FACE SIDE.

C. I. WILLIAMS Oct. 19, 1971 METHOD FOR SECURING FORMS FROM A POSITIONOF SAFETY 3 Sheets-Sheet 1 mvzzmoa Chester I. Williams ATTORNEY OriginalFiled June 5, 1967 C. l. WILLIAMS Oct. 19, 1971 3 Sheets-Sheet 2Original Filed June 5, 1967 J 1 S O 0 Rm 00 T ..H V m ll 7 r 4 m M S 6 hC ATTORNEY C. I. WILLIAMS Oct. 19, 1971 METHOD FOR SECURING FORMS FROM APOSITION OF SAFETY 3 Sheets-Sheet 5 Original Filed June 5, 1967 Fig. /4

Chester l. Williams ATTORNEY United States Patent Ofice Patented Oct.19, 1971 3,613,216 METHOD FOR SECURING FORMS FROM A POSITION OF SAFETYChester I. Williams, 347 Greenbriar S.E., Grand Rapids, Mich. 49506Original application June 5, 1967, Ser. No. 643,453, now Patent No.3,464,666, dated Sept. 2, 1969. Divided and this application Mar. 21,1969, Ser. No. 833,221

Int. Cl. B23p 19/00 U.S. Cl. 29-428 4 Claims ABSTRACT OF THE DISCLOSUREA mechanism for securing forms in position to develop a concretestructure in successive pours, including an anchor embedded in theprevious pour, and a coupling unit on the form, the coupling unit beingextendable to a position for engagement with means fixed with respect tothe anchor when the form is set back from the formed face of theconcrete, the coupling unit being retractable by a device controllablefrom the face side of said form to draw the form into engagement withthe formed face; and the method of securing a form from the face side.

CROSS-REFERENCE This application is a division of application Ser. No.643,453, filed on June 5, 1967, now Pat. No. 3,464,666.

SUMMARY OF THE INVENTION Concrete structures of large size are normallydeveloped in successive pours of five to ten feet in depth. Dams andabutments are common examples of this sort of construction, and the formpanels that define the outer vertical surfaces are secured in placethrough the use of anchors embedded in the concrete as each pour ismade. Once the concrete has hardened, those anchors become accessible assecuring points to hold the form in place as the next pour above ismade. The common manner of positioning the anchor devices for placementin the poured concrete results in the formation of an access socket inthe formed face, in which a heavy bolt can be engaged with the threadedand of the anchor. This bolt is conventionally engaged as the formstructure is suspended from a crane or equivalent device, and requiresthe presence of a workman on the outside of the form, which may beseveral hundred feet above ground. This is a definitely hazardousoccupation, and the placement of these form panels and the heavy boltsrequire considerable skill. The preferred form of the present inventionprovides a series of components that permit the form panel to be restedupon a short member secured directly to the anchor device, and thismember is engaged by an extendable coupling system mounted on the form.In the projected position, this coupling can be interengaged with thisfixed member secured to the anchor while the form is withdrawn from theface of the concrete by sufficient amount to permit the coupling to bemanipulated by a workman standing on the inside of the form on theconcrete surface. Once the interengagement has been completed, controlsare available to the workman standing in this same safe position whichwill cause the form to be drawn down onto the formed surface. Anarrangement is also provided by this invention for locking the formsecurely in this position. The primary advantages of this arrangementare in the saving of time in the placement of the forms, and in thedecrease in the hazard to the workman to the point that the higher payscales associated with hazardous operations are eliminated.

DETAILED DESCRIPTION The several features of the invention will beanalyzed in detail through a discussion of the particular embodi mentsillustrated in the accompanying drawings, in which:

FIG. 1 isa perspective view showing the placement of a form sectionunder the direction of a workman standing on the top of the previouspour of the concrete.

FIG. 2 is a perspective view on an enlarged scale showing the specialbolt attached to the anchor device embedded in the concrete.

FIG. 3 is a perspective view of the bolt from the opposite side fromthat shown in FIG. 2.

FIG. 4 is a sectional elevation showing the relationship of the anchordevice and the special bolt preparatory to receiving the coupling andthe locking pin.

FIG. 5 is a sectional elevation showing the first position of engagementof the coupling and the bolt, with the form in the withdrawn position.

FIG. 6 illustrates the same mechanism after the coupling has beenretracted to pull the form down against the formed face.

FIG. 7 is a view of the upper portion of the form showing the manner ofplacement of the anchors and the bolts in the space to be occupied bynewly poured concrete.

FIG. 8 is a section on the plane 88 of FIG. 7.

FIG. 9 is a section showing the coupling member.

FIG. 10 is a section on a horizontal plane showing the retractingmechanism for manipulating the coupling.

FIG. 11 is a section on an enlarged scale showing a locking device forsecuring the clamped condition of the form.

FIG. 12 is a section on an enlarged scale showing the locking device ofFIG. 11 in position.

FIG. 13 is a perspective view of the locking device.

FIG. 14 shows a modified form of the invention, and illustrates theplacement of the anchor device with a modified bolt segment.

FIG. 15 shows the fully assembled bolt utilizing the construction shownin FIG. 14.

FIG. 16 is a view on an horizontal plane showing the arrangementillustrated in FIG. 15.

FIG. 17 is a perspective view showing the use of a key for applicationof torque to remove the bolt segment from the anchor device.

Referring to FIG. 1 and the related views, the f r panels 20 and 21 areshown being placed in position preparatory to pouring a quantity ofconcrete on top of th previous pour 22. A workman is shown standing onthe top surface 23 of this pour, and the presence of the fullysecuredform 20 provides a considerable degree of safety for the workman as heguides the crane operator moving the panel 21 in position for theengagement of the securing mechanism. The sequence of this engagement isbest shown in FIGS. 4, 5 and 6. The form section 21 is of standard steelconstruction, and includes the face plate 24, a group of horizontalbeams 25-30 of channel-shaped cross section, and usually several pairsof channels in fairly close back-to-back relationship as shown at 31 and32 in FIGS. 10 and 12. These latter vertical beams extend across thehorizontal beams to transfer the forces from the pressure of theconcrete to the securing system.

The anchor devices 33 are conventional, and have crimped steel rodanchoring portions 33a. The threaded outer ends 3311 of these rods arefixed with respect to the anchor portion 33a, and are engaged by thespecial bolts shown in FIGS. 2 and 3. These bolts are indicatedgenerally at 35, and include a tapered inner portion 36, and a head 37.This head is slotted as shown at 38, and has a transverse hole extendingthrough the portions on both sides of the slot. A groove intersects theslot 38 to receive the offset head 41 of the locking pin 42. Prefer- 3ably, the slot 38 is flared at its outer extremity, as shown at 43, andthe outside surface on the head is provided with generally conicalsurfaces 44 and 45 to facilitate the interengagement of the couplingsystem.

The assembly of the bolt 35 and the anchors 33 are placed in positionwith the device shown in FIG. 7. Holes are provided in the face panel 24of approximately a thirty-second of an inch greater diameter than the11ameter of the cylinder defining the periphery of the head 37. Atubular socket 46 of approximately the same inside diameter as the holein the panel 24 is welded in place as shown in FIG. 7, and receives thehead 37 so that the inner extremity of the head is coplanar with theinside surface of the face plate 24. This'position is maintained throughthe interengagement of the pin 47, which may be identical to the pin 42shown in FIG. 2. The pin traverses suitable openings in the socket 46disposed to maintain the correct placement of the bolt. Thesebolt-anchor assemblies are usually placed in the form when thenewlypoured concrete is within two or three feet of the anchorpositions. This practice eliminates the danger of projecting anchorsinjuring a workman in the area back of the form.

The reciprocating coupling member 48 has a shank 49 traversing thetubular piston rod 50 moving within the cylinder 51. The end structure52 of the cylinder is secured to the vertical beams of the form bybolts, as shown at 53 and 54 in FIGS. 10 and 12. The construction of thecylinder 51 is conventional, and forms no part of the present invention.Normally, seals will be included in the end 52 and in the opposite end55 of the cylinder so that the tubular piston rod 50 may move throughthese walls without leakage of air or fluid, whichever is used in theparticular instance. The coupling device 48 is preferably blockedagainst rotation by being provided with a square configuration in crosssection, which provides top and bottom surfaces 56 and S7 and alsoparallel side surfaces 58 and 59. The top surface is disposed to bearagainst the bottom surface of the horizontal beam 25, and the sidesurfaces 58 and 59 are received between the beams 31 and 32, thuspreventing rotation of the coupling in both the retracted and extendedpositions. The tongue 60 is preferably receivable within the slot 38with about a thirty-second of an inch clearance, and the extended psition of the coupling shown in'FIG. is obtained by the application ofpressure in the line 61, which drives the piston 62 to the left, asshown in FIG. 10, carrying the tubular piston rod 50 with it. The line64 may be con sidered as a return, or exhaust line, under theseconditions. Pressure differentials between the lines 61 and 64 areobtainable by manipulation of the handle 65 associated with theconventional pump 66 shown in FIG. 1, resting on the top surface 23 ofthe previous pour of concrete. The unit 66 will normally include aselector valve which will determine which of the lines 61 or 64 shalldeliver pressure, the opposite functioning as a return line.

With the coupling 48 projected forward as shown in FIG. 5, the tongue 60is received within the slot 38. As soon as the form structure has beenaligned laterally to permit the hole 39 and the hole 67 to receive thepin 42, the placement of the pin can easily be made in the open spacebetween the formed face 68 of the concrete 22 and the face plate 24 ofthe form structure. The pin can be dropped in place by the workman as adirect manual operation, or the pin can be held in a suitable extensionwhich will permit him to do this from a standing position somewhat setback from the edge of the concrete. Once the pin is in position, asshown in FIG. 5, the application of pressure to the line 64 associatedwith the cylinder 51 will cause the form to be pulled down to the face68 in the position shown in FIG. 6. The groove 40 in the top of the bolt35 permits the offset end 41 of the pin to be received below the toptangent to the head 4 37, so that it does not interfere with the supportof the beam 25.

When the form has been drawn down securely into place, as shown in FIG.6, it may be desirable to lock the form in this position so that theplacement of it is not dependent upon the maintenance of pressure. Whenthe tubular piston rod 50 is withdrawn to the right, as shown in FIGS. 6and 12, the shank 49 and the surrounding portion of the tubular pistonrod 50 extend sufficiently from the end 55 of the cylinder 51 to receivethe U-shaped clip 69. The shank 49 is threaded, as shown at 70, at itsouter extremity. The washer 71 and the nut 72 are received over thisportion of the shank, and the nut 72 may be tightened over the clip 69to maintain the clamping action independently of the presence ofpressure within the cylinder 51. Since the form is held securely inposition by the presence of pressure in the cylinder at the time theclip 69 is installed and the nut 72 tightened, the manipulation of thesecomponents can be accomplished by a workman standing on a standardscaffold secured to the form panel without involving substantial hazard.

The method of securing a form panel in position by a clamping unitoperable from the concrete side of the form can also be carried outthrough the utilization of more conventional bolt and clamping devices,as shown in FIGS. 14 through 17. Since it is desirable to be able toplace the form on a support for alignment, and since it is equallydesirable that extensive projection from the formed face of the concreteis avoided so that the supports are not bent or displaced, the securingbolt generally indicated at 72 in FIG. 15 may be separated into an innerstub section- 73 and an outer, or securing section 74. This outersection is threaded over a major portion of its length for receiving thewing nut 75, and the junction between the inner and outer sections 73and 74 of the bolt may be interconnected through the use of male andfemale thread systems on the outer and inner sections, respectively, in-

terengaged as shown at 76. One-piece bolts may be used,

if desired. The bracket 77 spans across the gap between the beams 78aand 78b of conventional form structure similar to that shown in FIG. 1and is preferably bolted to the beams as shown to retain the bracket andthe outer bolt sections in engagement with the forms, thus saving muchrepeated handling of these members. This form structure is generallydesignated at 79, and rests against the formed surface 80 of theconcrete. The face plate 81 is provided with convenient access openings(not shown) through which an operator standing on the. top surface ofthe concrete 82 can reach through and connect the outer =bolt section 74with the inner bolt section 73 while the form structure 79 is res tingon the stub 73. Where one-piece bolts are used, it is even" possible toconnect.

these with the anchor devices from a positionon the concrete, prior to,or in connection with, the location of the form, or mount them on theform for sliding axially to and from an extended position, and rotatablyso they may be screwed into the anchor devices from the concrete side.The access openings in the face plate 81 are of any convenientconstruction to include a suitable removable cover to prevent theoutflow of poured concrete, and the cover can either be applied from theinside or outside of the form panels. In either event, the cover shouldbe flush with the inside face of the face plate 81 to preserve acontinuity of the formed surface 80.

The placement of the anchors and the inside sections 73 of the bolts isaccomplished through the arrangement shown in FIG. 14. The anchor device83 is engaged with threading on the tapered inner portion 84 of the boltsection 73, and the cylindrical portion 85 of the bolt section istraversed by a diametrical hole 86 for receiving the pin 87. The socket88 has an inside diameter approximately a thirty-second of an inchlarger than that of the cylindrical portion 85 of the bolt section 73,and a hole of similar diameter is provided in the face plate 81, withthe hole and the socket 88 forming a substantially continuous openingfor positioning the anchor 83 and the bolt section 73. After theconcrete has been poured about the anchor 83, and the concrete has set,the form can be removed after the pin 87 and the wing nut 75 have beenremoved. The form is backed off to the right, as shown in FIGS. 15 and16 a sufficient amount to disengage the socket 88 from the portion 85 ofthe bolt section. To keep foreign material out of the internal threadingin the bolt section 73, it is preferable to incorporate a plug 89 whichcan be removed by a pin traversing the diametrical hole 90.

A significant advantage of the arrangement shown in FIGS. 1 through 13is in the ability of the cylinder 51 to assist not only in pulling theform in place, but in inducing the lateral separation sufficient todisengage the form from the set concrete and the bolts received in thesockets 46 and 88. The application of pressure in the line 61 willinduce movement of the form from the FIG. 6 to the FIG. position, thusbreaking the face plate 24 from the formed face 68. This maneuver is, ofcourse, accomplished while the hook 91 of a crane is engaged with theform structure to maintain its support. The tap surface of the form iseasily Worked loose by the crane operator by controlling the directionof lift. The formed face is usually slanted (battered); and in suchcase, a vertical lift will tend to pull the form away from the face ofthe concrete. These forces, in conjunction with those applied by thecylinder 51, can easily back the form structure away enough to disengageit from the securing mechanism. Once it has been pushed back to the FIG.5 position, a workman can reach down through the gap between the formedface and the form structure with a tool, and withdraw the pins 42. Thecoupling members 48 can then be withdrawn by actuation of the pump 66,or by any convenient pressurized system that may control a series ofthese securing assemblies.

The particular embodiments of the present invention which have beenillustrated and discussed herein are for illustrative purposes only andare not to be considered as a limitation upon the scope of the appendedclaims.

In these claims, it is my intent to claim the entire invention disclosedherein, except as I am limited by the prior art.

I claim:

1. A method of securing a form to an anchor device accessible at theformed face of a pour of concrete, said method comprising:

supporting said form at a position set back from said formed face, andextending a coupling device inward from said form and coupling saidcoupling device to said anchor device; and

retracting said coupling device to pull said form to said formedsurface, said retracting being controlled from the face side of saidform.

2. A method as defined in claim 1, wherein said form is placed upon amember secured to said anchor and said coupling device engages saidmember.

3. A method of securing a form to an anchor device accessible at theformed face of a pour of concrete said method comprising:

supporting said form on a member fixed with respect to said anchordevice at a position set back from said formed face;

connecting said form to said anchor device with said References CitedUNITED STATES PATENTS 2,669,000 2/1954 Seemann 249-10 2,962,789 12/ 1960Williams 249-10 3,071,837 1/1963 Cerutti 24910 3,252,199 5/1966 Bossner264-33 X CHARLIE T. MOON, Primary Examiner

